Hydraulic Conductivity Measurement of Compacted Clay Soil ... 3_4_7.pdf · Hydraulic Conductivity Measurement of Compacted Clay ... Generally, flow chart of testing procedure performed

Journal of Earth Sciences and Geotechnical Engineering, vol. 3, no. 4, 2013, 125-145

ISSN: 1792-9040 (print), 1792-9660 (online)

Scienpress Ltd, 2013

Hydraulic Conductivity Measurement of Compacted Clay

Soil Liners for Waste Containment Structures

Putera Agung1, Budi Damianto2 and Sony Pramusandi3

Abstract

Method for in situ measurement of hydraulic conductivity (k) has been developed and

procedures for laboratory testing have been modified. Method and procedure are aimed to

obtain the significant hydraulic conductivity value and to avoid the effects of cracks or

dmax)

from standard and modified compaction test (ASTM D 698 – 91). Each test result uses a

sample taken from dry side; wet side and on optimum moisture content (wopt) or OMC.

First of all before the falling head test (ASTM D 1804 – 02/ASTM 180485 – 03) uses the

leachate liquid (Pondok Rajeg landfill), a solution of 0.005 CaSO4 is flown through the

sample and the hydraulic gradient equals 200. Hydraulic conductivity measurement of the

falling head test using a leachate liquid starts from the pore volume of flow > 2 until the

constant of hydraulic conductivity values is obtained. From the test results, the samples of

3” have hydraulic conductivity value in the range 10-10 to 10-9 cm/sec, and the samples of

10” have a range between 10-8 and 10-7 cm/sec. Generally, the research concludes that the

magnification of sample size influences hydraulic conductivity values on each falling

head test.

Keywords: Clay soil liner, leachate, falling head test, hydraulic conductivity.

1 Introduction

Compacted fine-grained soils (e.g. clay) are widely used as soil liners and cover the floor

of waste containment structures or landfills. The primary purpose is to minimize some

contamination to the natural ground water caused by the leachate permeation. The

hydraulic conductivity value of compacted clay liner is extremely importance (Daniel,

1987). A solid clay liner must have hydraulic conductivity values that are sufficiently low.

Measurements must be performed using the laboratory test on specimens or samples taken

from field, or using the large – scale measurement for in situ test techniques. Tests can be

1Civil Engineering – Politeknik Negeri Jakarta. 2Civil Engineering – Politeknik Negeri Jakarta. 3Civil Engineering – Politeknik Negeri Jakarta.

126 Putera Agung, Budi Damianto and Sony Pramusandi

conducted on the previous construction or prior to construction.

Several studies from literature shows that the hydraulic conductivity values of compacted

soil are influenced significantly by volume or dimension of block samples (Daniel, 1984;

Day and Daniel, 1985; Elsbury et al, 1988). From these studies, the measurements on

small samples produces the hydraulic conductivity values lower than the measurements

obtained from big samples. The measurement results on small sample also indicate the

values lower than the values of the large – scale of in situ test results. It can be concluded

that the measurements on small – samples cannot represent the existing field condition.

The article presents a logical alternative to conduct the measurement hydraulic

conductivity using the standard laboratory tests on the big enough of samples size to

simulate the existing field conditions. Laboratory tests can be performed rapidly and the

data results obtained more accurate. Furthermore, methods to perform standard laboratory

tests can be developed from the standard to ensure consistency of laboratory data results

through the Falling Head Test (ASTM D 1804-02/ASTM 180485-03). This research has

modified the Falling Head Test to measure the hydraulic conductivity from clay liner

samples. The research study has selected 2 (two) sizes or dimensions of the clay liner

samples, where they can be compared each other in the later. The study uses a sample of

clay liner diameter of 3” with the thickness of 1.0 cm and a diameter 10” with the

thickness 8.0 cm.

2 Background

2.1 Discrepancies Data Results of Hydraulic Conductivity Test

Daniel (1984) conducted and compared data results of hydraulic conductivity values in

laboratory using the different volume or dimension samples. Daniel (1984) found that

hydraulic conductivity values from big sample were generally reaching 10 to 1000 times

larger than small sample. Based on these results, Daniel (1984) concluded that main

problem relating with laboratory hydraulic conductivity tests on small samples is inability

to detect distribution of cracks; soft fissures at the time of test.

Day and Daniel (1985) concluded that hydraulic conductivity values from the big samples

were controlled by macro pores that were located between porous stone or sand and clay

samples. Elsbury et al (1988) also showed that the hydraulic conductivity from the larger

samples could reach values 4 to 5 times than hydraulic conductivity values measured in

small samples.

2.2 Similarities Data Results of Hydraulic Conductivity Test

Several investigators (Lahti et al (1987); Reades et al (1990); Gordon et al (1989);

Johnson et al (1990)) also observed the relationship between small and big sample on the

hydraulic conductivity at laboratory works. They found that generally, the previous

research results produce a wide variation of relationship between small and big samples

used on the laboratory testing.

2.3 Current Laboratory Works for Hydraulic Conductivity Test

The objective of current research study is also to control the quality Falling Head test

Hydraulic Conductivity of Compacted Clay Soil Liners 127

(ASTM D 1804 – 02/ASTM 180485 – 03) to measure the hydraulic conductivity from

laboratory tests. All samples are compacted using devices or tools of standard or modified

compaction test.

3 Testing Procedures

Experiments are conducted on samples with diameter 3” and thickness 1.0 cm; and

diameter 10” and thickness 8.0 cm, respectively. All test samples are conducted in the

laboratory using a constituted flexible – wall permeameter as shown as in Fig. 1.

3.1 Laboratory Test

The soil properties of samples are evaluated by general standard testing for fine grained

dmax) and optimum moisture content (OMC) or (wopt) was determined

by standard compaction test and both the data results were compared to the data result

from the modified compaction test; hydraulic conductivity (k) value measured by a

constituted flexible – wall permeameter.

Generally, flow chart of testing procedure performed at soil mechanic and foundation

laboratory of Civil Engineering of Politeknik Negeri Jakarta (PNJ) or State Polytechnic

Jakarta is shown on Figure 2 Diameter of clay samples as soil liners used in this study is 3”

(inches) and 10” (inches). Study uses standard solution of 0.005 N CaSO4 during

saturation process.


Figure 1: A constituted flexible – wall permeameter


Figure 2: Flow chart research study


Table 1: General soil properties of Beji clay

No. Soil properties Result

1. Natural water content (w) (%) 45.7

2. Bulk density ( m) (gr/cm3) 1.6

3. Specific gravity (Gs) 2.68

4.

Atterberg limits:

a. Liquid limit (LL), (%) 90.0

b. Plastic limit (PL), (%) 44.8

c. Plasticity index (PI), (%) 45.2

d. Shrinkage limit (SL), (%) 24.9

5. Sieve analysis (weight of 500 gr)

passed on sieve No. 200 (gr) 491,1

6. Hydrometer analysis

(% diameter < 0.002 mm) (%) 80 – 90 (clay)

The saturation process is stopped when the pore volume of flow larger than or equals 2.0,

and then the solution of 0.005 N CaSO4 is substituted by leachate. Clay soils used in this

study are taken from around Kecamatan Beji, Kota Depok and leachate sample was taken

from waste disposal area (WDA) Pondok Rajeg, Cilodong, Sukmajaya. Soil properties

results are shown in Table 1 and the chemical contents of leachate from Depok landfill

(WDA) are shown in Table 2.

The chemical contents of Depok clay are shown in Table 3 where all samples were tested

at Laboratory of Chemical Department, University of Indonesia (UI), Depok Campus.

Based on the Table 3, it can be predicted that all clays mineral are very tiny crystalline

substances evolved primarily from chemical weathering of certain rock-forming minerals

(Holtz and Kovac, 1981). Chemically, they are hydrous aluminosilicates plus other

metallic ions. From chemical composition, the soil has kaolinite or illite minerals in a

large fraction; while montmorillonite exists in a small fraction.

Based on Table 1, mean natural water content of soil samples is 45.7 %, where according

to Bowles (1977) the water content is less than 60 % for dry surface condition. Specific

gravity (Gs) is 2.68, based on NAFAC (1971) the specific gravity of clay is between 2.5 to

2.9. Soil has mean grain size less than 0.002 mm and it can be classified as MH & OH

based on Unified Soil Classification System (USCS). From Table 2, it can be known that

the leachate has the high concentration of BOD and COD. In addition to the leachate has

a high value of fatty acid; pH; smell; the leachate also has an ammonia, N organic, Zn,

Mg, Cl, Pb and small number of the other of heavy metal. Based on geotechnical and

geology map for Kota Depok, soil layers at Beji location is red latosol with fine texture

and came from uncemented of andesite tuff (initial of soil layer is 28) (Figure 3).


Table 2: Chemical contents of leachate

Chemical elements unit

Alkalinity PP 10.0

MD 22.2

pH 8.2

CO2 0.0

Cl 15.0

Water hardness 13.2

Total of CaCO3 22.2

Ammonia (NH4-N) 51.6

Nitrate (N03-N) 2.3

Nitrite (NO2-NO) 0.5

Phosphate (PO4) 0.9

Sulphate (SO4) 44.5

DO / DIS Oxygen (O2) 4.8

COD / dichromate 1,326.0

BOD 785.0

Detergent 3.9

Phenol -

Magnesium (Mg) 7.0

Plumbum (Pb) 0.4

Zinc -

(Source : Dinas Kebersihan dan Pertamanan tahun 1996, Pemda Kotatip Depok)

Note: unit (mg/l), excepted for pH

3.2 Data Results Analysis

Mean of water line reading (0.005N CaSO4 solution and leachate) at the cylinder of

gauge – glass (or burette) on falling head test (ASTM) were observed and recorded, then

the hydraulic conductivity (k) values are determined by the equation:

1

2

ha .Lk 2.303 log

A.t h (1)

All measurements of hydraulic conductivity (k) are plotted on graphic relationship

between hydraulic conductivity (k) vs. time (day) for reading.


Table 3: Chemical content of Depok clay

(Laboratory of chemical department – University of Indonesia)

No. Chemical

element Result Unit Method

1 Magnesium (Mg2+) 194.0 ppm AAS

2 Sodium (Na+) 70.5 ppm AAS

3 Potassium (K+) 245.3 ppm AAS

4 Calcium (Ca++) 14.2 ppm AAS

5 Chloride (Cl-) 37.9 ppm Ion-meter

6 Sulphate (SO42-) 261.3 ppm Spectrometer

7 Silicate (SiO2) 49.0 % Gravimetric

8 pH 7.6 - pH meter

Note: ppm = part per million

Figure 3: Identification of soil sample based on the geotechnical and geology map of

Kotatip Depok, West Java (2005)

4 Results and Discussion

4.1 Characteristic of Compacted Clay

Data results of standard compaction test are shown in Figure 3. Hydraulic conductivity (k)

are evaluated with using 3 (three) zones of water content, such as: dry side; optimum

point; and wet side as shown as in Figures 4a and 4b based on relationship between water

content and particle orientation in standard compaction test as well as the suggestion from

Lambe (1958).


4.2 Hydraulic Conductivity Values

The relationships between hydraulic conductivity of Beji clay liner and time are shown in

Figure 5 (diameter of sample 3” and thickness 1.0 cm) and Figure 6 (diameter of sample

10” and thickness 8.0 cm). 3 (three) condition of water content were taken from condition

of dry side; optimum point (OMC); and wet side from the results of standard compaction

test (Figures 4a and 4b).

Figure 3: Results of standard vs. modified test


Figure 4a: Samples from location (1)

Figure 4b: Samples from location (2)


Figure 5: Hydraulic conductivity (k) vs. time (day) on sample of diameter 3”

and thickness 1.0 cm

Figure 6: Hydraulic conductivity (k) vs. time (day) on sample of diameter 10”

and thickness 8.0 cm


4.2.1 Dry side condition where wc < wopt

Figures 5 and 6 show the influences of leachate to hydraulic conductivity values for

compacted clay using standard compaction test based on the water content in dry side

zone. In both figures indicate that hydraulic conductivity values decrease after solution

standard of 0.005 N CaSO4 substituted by leachate. Hydraulic conductivity values back to

enlarge gradually, however after few days, hydraulic conductivity clay liner tends to

constant and slightly decreased.

The deriving process of hydraulic conductivity value was caused by Na+ cation of

leachate, then it would be occurred by attracted force between Na+ and Ca2+ contained in

solution of 0.005 N CaSO4. The reduction of cation valence on pore water (based on

Gouy – Chapman Equation) caused double layer thickness become to enlarge, so that

flow line becomes small. On the contrary, the raising of hydraulic conductivity value was

caused by increasing electrolyte concentration in pore water, furthermore thickness of

double layer becomes small, and finally to enlarge flow line. However, the values of

hydraulic conductivity by using the leachate are always smaller than from the beginning

when using solution of 0.005 N CaSO4.

Generally, all samples of compacted clay liner (diameter 3” thickness 1.0 cm; and

diameter 10” thickness 8.0 cm) in dry side zone produces many pores and particle

orientation more flocculated, so that double layer become to enlarge due to increase ion

concentration and very difficult back to decrease. The decreasing of hydraulic

conductivity values may be caused by solid particles contained in leachate and covers or

catches all pores of compacted clay sample, finally to decrease flow line.

4.2.2 OMC point condition where wc = wopt

Hydraulic conductivity values of OMC condition are smaller than dry side condition and

takes time any longer than before. Thus, it would be concluded that leachate is hard to

penetrate or pass through the soil pores (extra or intra particle), it can be followed air

content more and more decreasingly. However, after a few time, hydraulic conductivity

values back to increase gradually closing to previous hydraulic conductivity value.

Because of degree of density produced on OMC is higher than dry or wet sides, soil pores

become small, and particle orientation tends to more dispersed. The deriving of cation

valence in pore water was caused Na+ cation contained of leachate. For this condition,

thickness of double layer and particle orientation of clay liner are constant caused

increasing concentration of ion. It can be concluded that the flow line can be slightly

retained by decreasing of void ratio or porosity of the compacted clay in OMC condition.

And, the hydraulic conductivity becomes smaller caused by the retained flow.

4.2.3 Wet side condition where wc > wopt

For this condition is almost same with optimum point. It would be caused by more

dispersed particle orientation in a little stream flow, so that thickness of double layer of

clay liner is constant. The deriving of hydraulic conductivity value is caused by solid

particle contained leachate and covering pores of clay liner, and furthermore flow line

become small.


4.2.4 Relationship between k – d – w

According to hydraulic conductivity test results using a constituted flexible – wall

permeameter and diameter sample of 3” and 10” with different thickness, generally it

shows that leachate strongly influences hydraulic conductivity (k) value of clay liner.

Some fluctuations of hydraulic conductivity value caused leachate flow are very

influenced by particle orientation of clay liner. Hydraulic conductivity value at dry side

zone is always larger than wet side zone, although both zones are compacted with same

energy. Typical relationships between k; dry density (d); and water content (w) for

sample size of 3 are shown at Figures 7 (a and b). And, typical relationships between k;

dry density (d); and water content (w) for sample size of 10 are shown at Figures 8 (a and

b).

Figure 7a: Relationship between k vs. d for sample diameter of 3”

and thickness of 1.0 cm

From Figures 7 and 8, it can be concluded that the dry density (d) and water content (w)

values for 3 (three) condition of samples, such as: dry; OMC; and wet conditions,

respectively, can influence hydraulic conductivity values. The hydraulic conductivity

values are more decreased when dry density and water content are more and more

increased. Hydraulic conductivity values on dry side are higher the values on wet side.


Figure 7b: Relationship between k vs. w for sample diameter of 3” and thickness of 1.0

cm

Figure 8a: Relationship between k vs. d for sample diameter of 10” and thickness of 8.0

cm


Figure 8a: Relationship between k vs. w for sample diameter of 10”

and thickness of 8.0 cm

4.3 Representative of sample size

From both samples (diameter 3” and 10” with the different thickness), significantly it can

be known that there are some difference of hydraulic conductivity values when both

samples was flown by 0.005 N CaSO4 and leachate (Daniel, 1984; Day and Daniel, 1985;

Elsbury et al, 1988). And, generally, it can be concluded that measurements performed on

small samples produce some deviations of hydraulic conductivity results if they are

compared by the bigger samples. Table 4 shows the results of using small and big samples

for the measurement of hydraulic conductivity. Figure 9 shows that the effects of

enlargement of clay liner samples from 3” to 10”, the hydraulic conductivity become a

small increase, and the hydraulic conductivity values can vary from 10 to 100 times of the

sample size smaller for larger sample.

From Figure 9 shows that hydraulic conductivity values on diameter sample of 3” tends to

occur some deviations and moreover it can close to zero (0). Whereas the sample of 10”

diameter is relatively more reflects existing condition in field, although it requires

large-scale test in field. In such a way that it can be concluded generally, the size of

sample in falling head test strongly influences hydraulic conductivity values on the dry;

OMC; and wet conditions.


Table 4: Comparison of hydraulic conductivity values between the sample sizes of 3” and

10” diameter

Sample conditions

Hydraulic conductivity (k) (cm/sec) values

Diameter of sample 3” Diameter of sample 10”

Flow line 0.005 N CaSO4 Leachate 0.005 N CaSO4 Leachate

Dry side 1.117 . 10-8 5.377 . 10-9 3.568 . 10-7 2.104 . 10-7

OMC 9.920 . 10-10 7.681 . 10-10 2.422 . 10-7 9.554 x 10-8

Wet side 5.756 . 10-10 3.561 . 10-10 9.733 . 10-8 4.150 . 10-8

Figures 9: Hydraulic conductivity (k) vs. time (day)

The results of measurement show that the difference of hydraulic conductivity values

from sample diameter of 3” and 10”. The values obtained for sample diameter of 3” are

1.117 x 10-8 to 5.756 x 10-10 cm/sec for flow of 0.005 N CaSO4 and 5.377 x 10-9 to 3.561

x 10-10 cm/sec for flow of leachate. Whereas the test using enlargement to sample

diameter of 10”, hydraulic conductivity values reach 3.568 x 10-7 to 9.733 x 10-8 cm/sec


for flow of 0.005 N CaSO4 and 2.104 x 10-7 to 4.150 x 10-8 cm/sec for flow of leachate.

According to Benson et al, 1998, that sample having small diameter (diameter ≤ 3”)

cannot show the existing condition of field, the enlargement of sample size are always

followed by the change of hydraulic conductivity values significantly.

From both sizes of sample of 3” and 10” shows the significant difference to the hydraulic

conductivity values when they are flown by standard solution of CaSO4 and leachate. It

can be concluded that these results can support some previous evaluation of hydraulic

conductivity performed by Daniel (1984); Day and Daniel (1985); and Elsbury et al

(1988). All measurement results of hydraulic conductivity are found that generally, the

measurements conducted by smaller samples obtain the deviation values significantly

from the larger size of samples tested by falling head test. The sample sizes of 10” are

more representative and closes to field condition, although these results has to be

compared to the results of the in situ test. Thus, it can be concluded that the enlargement

of sample size can influence the hydraulic conductivity values.

5 Discussion

Values of hydraulic conductivity are also depended on the characteristic of leachate liquid.

From the observation in study area, type of waste material where the leachate obtained

consists of 45.12 % plastic material; and 33.28 % paper material; the percentage for other

materials are shown in Fig. 10. These kind of waste materials shows that source of waste

material were come from settlement area; road or highway; industries; building or office

building; old or new building rubble; and waste material from building renovation. The

other of waste material properties are: water content 44 %; weight volume around 0.20

gr/cm3; volatile content 84 %; ash content 16 %; and temperature between 30 to 34o C.

From observation to the falling head laboratory test, the values of hydraulic conductivity

can be influenced by the leachate containing the more solid material composition. The

solid material has the potential to reduce the pore space of compacted clay during flow

takes place. It can be assumed that the more dense material accumulates and impedes the

flow, so that the pore space reduces into smaller.

The previous researcher concluded that from 3 (three) of falling head testing for soil liner

performed using the magnification of samples were obtained mean difference of hydraulic

conductivity values between 10 to 100 times than the values reached for smaller samples.

Some constraints existed for the testing of smaller samples can usually cause any

conditions of soil sample becoming more solid, so that almost the pore spaces are more

compressed. However, this reality becomes more difference when the testing uses bigger

size of samples. The bigger size of samples can be influenced by soft or wide fissures;

side spaces condition which are not compressed; and or some hydraulic problems during

testing which are available on the larger size of samples (Daniel, 1984). Furthermore, Day

and Daniel (1985) concluded that from 2 (two) prototypes of hydraulic conductivity soil

liner testing of the big size samples were produced the pore spaces larger than the smaller

samples. It can be concluded that all samples which have the smaller size are not

representative for using in the clay liner design.


Figure 10: Waste material composition from landfill of Pondok Rajeg, Depok

Elsbury et al (1988), Lahti et al (1987), Johnson et al (1990) and Reades et al (1990) were

found that the testing using the larger size of samples had the small correlation when they

were compared by the next testing using the smaller size of samples. They also found that

from the hydraulic conductivity results of the larger size samples were obtained 3 to 4

time bigger than the values using the smaller size of samples. It can be suggested that the

evaluation of hydraulic conductivity in laboratory tests have to be upgraded using the

sample in larger size, so that it can be produced the hydraulic conductivity values closing

to the existing condition of field area.

In situ test has to be conducted to measure the hydraulic conductivity values using the

percolation test or some similar tests; and to find some critical changes for determination

the exact values of hydraulic conductivity used in the design of clay liner. With using in

situ test, it can be produced the the representative sample size and magnification factor of

the hydraulic conductivity values for the laboratory test, so that the designer can predict

the hydraulic conductivity values closer to the existing condition in the field area.

However, the in situ tests become impractical cases caused by some disturbance during

the measurement, such as: the traffic loading and unloading at landfill area; digging area;

etc. From the Equation (1) in practical implications, all other factors held constant,

Darcy’s law is valid, although a number of proposals (Hansbo, 1960; Swartzendruber,

1962a; 1962b; 1963) have been made for alternative relationships to Darcy’s law to

describe the relationship between flow velocity and gradient. Others (Florin, 1951; Roza

and Kotov, 1958; Hansbo, 1960; Barden and Berry, 1965, Mitchell and Younger, 1967;

Schmidt and Westmann, 1973) have studied the implications of threshold gradient and


nonlinearity on seepage and consolidation. Gradient used in laboratory determinations of

hydraulic conductivity and consolidation behavior are higher than is the case for the field

conditions under study. A gradient-dependent hydraulic conductivity in such a case could

be the cause of substantial discrepancies between laboratory – measured and field values

of coefficient of consolidation.

The other macro tests are required to understand subsequently some changes of the

hydraulic conductivity values caused by the changes of consolidation parameter, such as:

index of compression (Cc); coefficient of consolidation (Cv); index of volume changes

(mv); and the volume changes of waste material working on the solid clay liner. The

important observations are the deviations of hydraulic gradient caused by the damage of

the layer between waste material and clay liner (e.g. geotextile, etc), deviations of

hydraulic gradient can influence hydraulic conductivity values. To find out in more detail

of clay particle orientation after the flow line of leachate, it would be required some micro

tests, such as: scanning electron microscope (SEM); electron microscope; X-ray test, etc.

These tests are needed to know the condition of pore spaces (intra or extra particle). From

these test, it can be learned that the hydraulic conductivity depends on clay content;

sedimentation procedure; compression rate; and electrolyte concentration. Subsequent

behavior is quite sensitive to the type and concentration of electrolyte used for permeation

and the total throughput volume of permeant (Hardcastle and Mitchell, 1974). Mitchell

and Younger (1967) suggested to study the particle migrations, as reflected by changes in

pore pressure distribution with time in the direction of flow. Some observations to change

of chemical composition from samples after the stream of leachate are also required to

find out the change of mechanical properties or shear strength parameters of the clay liner,

such as: cohesion (c); friction angle (); and the others.

Finally, from several tests performed to measure hydraulic conductivity values for solid

clay liner in landfill area, there are many information which has to be known, such as:

size of sample; density; clay particle orientation; clay content, etc. However, the

important factor in laboratory test performance related with the selected sample size are

some variables depended on sample preparation; devices; and laboratory procedure. The

previous study on field test has to be collected, so that it can be designed the

representative solid clay liner size to monitor the changes of the hydraulic conductivity

after construction.

6. Conclusions and recommendations

The size of representative sample for measurement of hydraulic conductivity of

compacted soil liner (clay soil from Beji-Kota Depok) depends on the method and quality

of construction. If the soil is compacted poorly (e.g. dry of the line of optimum or with

low compaction effort), the representative sample size has to be large. However, when the

soil is well compacted (wet of the line of optimum or with high compaction effort), the

representative size is small. However, a key factor controlling the representative sample

size is the results of field test.

The experimental results suggest that field – scale hydraulic conductivity can be measured

on specimens with a diameter of at least 10” and a thickness of 8.0 cm for a wide variety

of construction conditions. Block samples size are recommended for measurement the

hydraulic conductivity in situ test after construction. Some observations before the filed


tests are required to avoid some disturbance during measurement the hydraulic

conductivity.

The influence samples size of diameter 3” to 10” on experiments using falling head tests

can produce the hydraulic conductivity values significantly where enlargement factor

around 10 – 100 times.

Representative density of clay liner for waste containment structures can be selected by

compaction condition using water content of wet side 40 % until liquid limit value ((LL)

≤ 90%), definitely with controlling workability compaction in field, because the clay soil

is very hard to compact on high water content.

Prevention of leachate infiltration to high water table at around of waste containment

structures can use clay liner with dry density (γd) = 1.261 gr/cm3 and wet side condition

(40 %). Moreover, if it would be required, it also can use optimum point condition ((γd) =

1.495 gr/cm3 and optimum moisture content = 25.50 %) added leachate filter material

using coarse grained layers; geotextile; etc.

The monitoring works are required to guarantee the constant of hydraulic conductivity

during life time of planning. Consequences, in situ tests have to be conducted

periodically. Some other constraints that can influence the measurement of the hydraulic

conductivity should be avoided such as: a traffic loading and unloading of waste material;

and the changes of waste material volume.

ACKNOWLEDGEMENTS: The author wish to express their sincere gratitude to the

P2M of Directorate of Higher Education, Department of National Education Republic of

Indonesia and Politeknik Negeri Jakarta or State Polytechnic of Jakarta (PNJ) for research

fund of “Dosen Muda” 2007 based on contract No.003/SP2H/PP/DP2M/III/2007; the city

government of Depok; and Laboratory of chemical department – UI. Since their support,

the authors can give valuable contribution to research development of geotechnical

engineering in PNJ generally, and problem solving for determination of hydraulic

conductivity parameter of solid clay liner especially, also for the basic design of waste

containment structure of Pondok – Rajeg, Kota Depok. The research has suggested to the

representative sample size for solid clay liner at laboratory works.

References

[1] Benson, C., H., and Hardianto, F., S, Representative sample size for hydraulic

conductivity measurement of compacted soil liners for waste containment structures,

Proceeding: Geoteknik di Indonesia Menjelang Milenium ke – 3, 1998, pp. VII –

33 – VII – 52.

[2] Barden, L., and Berry, P.L, Consolidation of normally consolidated clay. Journal of

the soil mechanics and foundation division, ASCE, 91, No. SM5, (1965), 15 – 36.

[3] Daniel, D., E, Predicting hydraulic conductivity of clay liners. Journal of

Geotechnical Engineering, ASCE, 110(2), (1984), 285-300.

[4] Daniel, D., E, Earthen liners for land disposal facilities. Geotechnical Practice for

Waste Disposal ’87, GSP No. 13, ASCE, (1987), 21 – 39.

[5] Dinas Kebersihan dan Pertamanan. Buku data Pemda Kotatip Depok, (1996).

[6] Pemda Kotatip Depok. Peta Geoteknik dan Geologi Kotatip Depok, Jawa Barat.

(2005).


[7] Elsbury, B., R. et al, Field and laboratory testing of compacted soil liner,” Report to

USEPA for Contract No. 68-03-3250, (1988), Cincinnati, Ohio.

[8] Florin, V.A, Consolidation of earth media and seepage under conditions of variable

porosity and consideration of the influence of bound water. Izvestia Academy of

Science, USSR, Section of Technology Science, No. 11, (1951), 1625 – 1649.

[9] Hansbo, S, Consolidation of clay with special reference to the influence of vertical

sand drains. Proceeding, 18, Swedish Geotechnical Institute, Stockholm, (1960).

[10] Hardcastle, J.H., and Mitchell, J.K, Electrolyte concentration-permeability

relationships in sodium illite-silt mixtures. Clays and clay minerals, 22(2), (1974),

143 – 154.

[11] Johnson, G., et al, Field verification of clay liner hydraulic conductivity. In Waste

Containment System: Construction, Regulation and Performance, GSP, No. 26,

ASCE, New York, (1990), 226 – 245.

[12] Lambe. The Structure of compacted clay, JSMFD, ASCE, 84, No. SM 2, (1958).

[13] Mitchell, J.K., and Younger, J.S, Abnormalities in hydraulic flow through

fine-grained soils. ASTM Special Technical Publication 417, (1967), 106 – 141.

[14] Lahti, L., et al, Quality assurance monitoring of a large clay liner, Geotechnical

Practice for Waste Disposal ’87, GSP N0. 13, ASCE, (1987), 640 – 654.

[15] Reades, D, et al, Detailed history of clay liner performance. In Waste Containment

Systems Construction, Regulation and Performance, GSP No. 26, ASCE, New York,

(1990), 156 – 174.

[16] Roza, S.A., and Kotov, A. L, Experimental studies of the creep of soil skeletons.

Zapiski Trudonovo Krasmorro Znamemo gornono institute um G. A. Plakhanova,

34(2), (1958), 203 – 213.

[17] Swartzendruber, D, Modification of Darcy’s law for the flow of water in soils, Soil

science, 93, (1962a), 27 – 29.

[18] Swartzendruber, D, Non-Darcy’s behavior and flow behavior in liquid-saturated

porous media. Journal of Geophysical Research, 67(13), (1962b), 5205 – 5213.

[19] Swartzendruber, D, Non-Darcy behavior and flow of water in unsaturated soils. Soil

science of America, Proceedings, (1963), 491 – 495.

[20] Schmidt, J.D., and Westmann, R.A.. Consolidation of porous media with non-Darcy

flow, Journal of the Engineering Mechanics Division, ASCE, 99, No. EM6, (1973),

1201 – 1216.

Documents

Hydraulic Conductivity Measurement of Compacted Clay Soil ... 3_4_7.pdf · Hydraulic Conductivity Measurement of Compacted Clay ... Generally, flow chart of testing procedure performed